Apparatuses including power electronics circuitry, and related methods of operation

ABSTRACT

Apparatuses including power electronics circuitry are provided. The power electronics circuitry includes at least one power converter that is coupled to a DC bus. Moreover, in some embodiments, the at least one power converter is configured to regulate a voltage of the DC bus. Related methods of operating an apparatus including power electronics circuitry are also provided.

RELATED APPLICATIONS

The present application claims the benefit of U.S. Provisional PatentApplication No. 62/451,174, filed Jan. 27, 2017, and U.S. ProvisionalPatent Application No. 62/527,715, filed Jun. 30, 2017, the disclosuresof which are hereby incorporated herein in their entirety by reference.Moreover, the present application is related to U.S. patent applicationSer. No. 14/870,126, filed Sep. 30, 2015, now U.S. Pat. No. 9,829,899,the disclosure of which is hereby incorporated herein in its entirety byreference.

FIELD

The present disclosure relates to utility meters and power electronics.

BACKGROUND

High penetration of Distributed Energy Resources (DERs), especially atlow-voltage networks may introduce power quality problems such asvoltage sags and swells, and may exacerbate voltage harmonics on a grid.Conventionally, these negative effects of DERs were mitigated bycentralized bulk devices at the medium-voltage level, such as at a plantor a substation. For example, static compensators (STATCOMs) and staticVAR compensators (SVCs) may be provided at a central level to regulateline voltage through reactive power control. These semiconductor-baseddevices may actively regulate the reactive current injected into thegrid and may provide faster and finer regulation thanmechanically-switched voltage regulators such as Line Tap Changers(LTCs). These systems, however, may fall short of resolving problemsarising at the leaf end of a distribution network due to massive DERpenetration, especially in residential and commercial markets. Forexample, due to their centralized existence at the medium-voltage level,the visibility of such systems to problems locally occurring at lowvoltages may be limited. Also, as low-voltage distribution networks havesmaller ratios of reactance to resistance (X/R ratios), theeffectiveness of reactive current injection may be muted.

SVCs on a low-voltage network (μ-SVCs) may overcome some of the problemsof centralized bulk devices at the medium-voltage level, as thedistributed deployment of μ-SVCs may mitigate negative effects of DERsat the source, thus blocking their propagation to the medium-voltagenetwork. μ-SVCs, however, may be bulky, may offer limited power control,and may fail to adequately compensate for grid voltage harmonics.

SUMMARY

It should be appreciated that this Summary is provided to introduce aselection of concepts in a simplified form, the concepts being furtherdescribed below in the Detailed Description. This Summary is notintended to identify key features or essential features of thisdisclosure, nor is it intended to limit the scope of the presentinventive concepts.

Various embodiments of the present inventive concepts include anapparatus including a housing. The apparatus may include electricutility meter circuitry in the housing and configured to measure usageof electricity supplied by an electric utility to a premise of acustomer of the electric utility. Moreover, the apparatus may includepower electronics circuitry in the housing. The power electronicscircuitry may include a dynamic Watt-VAR compensator including a gridinterface switched mode power converter that is coupled to an AC bus andto a DC bus and that is configured to regulate a voltage of the DC bus.

In various embodiments, the grid interface switched mode power convertermay include bidirectional power converter circuitry that is coupled tothe AC bus and to the DC bus and that is configured to operate in both apower inverter mode and a power rectifier mode.

According to various embodiments, the apparatus may be a Premise EnergyRouter (PER) that includes the electric utility meter circuitry and thepower electronics circuitry at or adjacent the premise of the customer.The PER may be downstream from a substation that serves the premise ofthe customer. The voltage of the DC bus that the grid interface switchedmode power converter is configured to regulate may be 24 Volts to 2,000Volts. Moreover, a switching frequency of the grid interface switchedmode power converter may be 10 kilohertz or higher.

In various embodiments, the premise may be a residential premise of thecustomer, and a voltage of the AC bus that is coupled to the gridinterface switched mode power converter may be 120 Volts, 208 Volts, or240 Volts. The 120 Volts, 208 Volts, or 240 Volts may be a single-phase,split-phase, or three-phase voltage.

According to various embodiments, the DC bus may be in the apparatus andmay be a shared DC bus that is coupled to a plurality of DC powergeneration and/or DC energy storage elements at the premise of thecustomer. The grid interface switched mode power converter may beconfigured to convert DC power received from the plurality of DC powergeneration and/or DC energy storage elements via the shared DC bus intoAC power. Moreover, the grid interface switched mode power converter maybe further configured to inject current to a Point of Common Coupling(PCC) that is between an AC grid to which the apparatus is coupled and aload of the premise of the customer. In some embodiments, the currentmay include a direct fundamental and harmonic current and a quadraturefundamental and harmonic current, and the PCC may be an AC PCC.

In various embodiments, the grid interface switched mode power convertermay include single-phase, split-phase, or three-phase powerbidirectional inverter-rectifier circuitry that is coupled to the sharedDC bus. Moreover, the plurality of DC power generation and/or DC energystorage elements may be coupled to the shared DC bus via a plurality ofswitched mode power converters, respectively. In some embodiments, theplurality of DC power generation and/or DC energy storage elements mayinclude a DC power generation element including a solar photovoltaic(PV) system or a fuel cell, and may include a DC energy storage elementincluding a battery or a capacitor. In some embodiments, the pluralityof switched mode power converters may include first and second DC-to-DCpower converters that are coupled to the shared DC bus. The solar PVsystem or the fuel cell may be coupled to the first DC-to-DC powerconverter, and the battery or the capacitor may be coupled to the secondDC-to-DC power converter.

According to various embodiments, the apparatus may be free of anymechanical circuit breaker and free of any step-up or step-down ACtransformer. Additionally or alternatively, the apparatus may include aDC link capacitor, or a bank of capacitors, coupled to a battery energystorage system.

Various embodiments of the present inventive concepts include a methodof operating an apparatus connected between a utility secondary serviceof an electric utility and a wiring connection of a customer at apremise of the customer. The method may include measuring, usingelectric utility meter circuitry of the apparatus, usage of electricitysupplied by the electric utility to the premise of the customer.Moreover, the method may include regulating, using a grid interfaceswitched mode power converter of power electronics circuitry of adynamic Watt-VAR compensator of the apparatus, a voltage of a DC bus inthe apparatus.

According to various embodiments, the DC bus may be a shared DC bus thatis coupled to a plurality of DC power generation and/or DC energystorage elements at the premise of the customer. Moreover, theregulating may include operating a power inverter mode of the gridinterface switched mode power converter, while the grid interfaceswitched mode power converter is coupled to the shared DC bus and isshared by the plurality of DC power generation and/or DC energy storageelements. In some embodiments, the regulating may include operating apower rectifier mode of the grid interface switched mode powerconverter, while the grid interface switched mode power converter iscoupled to the shared DC bus and is shared by the plurality of DC powergeneration and/or DC energy storage elements.

In various embodiments, the grid interface switched mode power convertermay be coupled to an AC bus. The method may include detectingpreexisting harmonics at an AC Point of Common Coupling (PCC), anddetermining harmonic current to inject to the AC PCC to compensate forthe preexisting harmonics. In some embodiments, the measuring and theregulating may be performed while the apparatus is downstream from asubstation that serves the premise of the customer and without using anystep-up or step-down AC transformer in the apparatus. Moreover, thevoltage of the DC bus may be 24 Volts to 2,000 Volts while performingthe regulating, and a switching frequency of the grid interface switchedmode power converter may be 10 kilohertz or higher while performing theregulating.

According to various embodiments, the premise may be a residentialpremise of the customer, and the measuring and the regulating may beperformed while the apparatus is at or adjacent the residential premiseof the customer. Additionally or alternatively, the regulating mayinclude operating the grid interface switched mode power converter as avoltage source, while a plurality of switched mode power converterscoupled to the DC bus operates in a current source mode or in a voltagesource mode.

An apparatus, according to various embodiments of the present inventiveconcepts, may include power electronics circuitry therein. The powerelectronics circuitry may include a dynamic Watt-VAR compensatorincluding bidirectional inverter-rectifier circuitry that is configuredto inject current to an AC PCC. The power electronics circuitry mayinclude a DC bus coupled to both a DC power generation system and a DCenergy storage device at a premise of a customer of an electric utility.Moreover, a switching frequency of the power electronics circuitry maybe 10 kilohertz or higher. In some embodiments, the apparatus mayinclude electric utility meter circuitry therein that is configured tomeasure usage of electricity supplied by the electric utility to thepremise of the customer.

Various embodiments of the present inventive concepts include a PER ator adjacent a premise of a customer of an electric utility. The PER mayinclude a housing and a DC bus in the housing. Moreover, the PER mayinclude a plurality of switched mode power converters in the housing,coupled to the DC bus, and configured to interface with a plurality ofDERs, respectively, at the premise of the customer,

According to various embodiments, the plurality of DERs may include anenergy storage device at the premise of the customer. The plurality ofswitched mode power converters may include an energy storage switchedmode power converter coupled to the DC bus and to the energy storagedevice. Moreover, the energy storage switched mode power converter maybe configured to insert synthetic inertia for a distribution grid towhich the PER is coupled. In some embodiments, the energy storage devicemay be an ultracapacitor or a battery.

In various embodiments, the PER may include communications circuitryconfigured to provide communications, via a field message bus, betweenfirst and second ones of the plurality of switched mode powerconverters. Additionally or alternatively, the PER may include a gridinterface switched mode power converter coupled to the DC bus. The gridinterface switched mode power converter may be configured to adjust orhold a voltage of the DC bus. The grid interface switched mode powerconverter may be a power semiconductor device that is configured toswitch at a frequency of 10 kilohertz or higher.

According to various embodiments, the PER may include DC meter circuitryconfigured to measure DC power, and AC meter circuitry configured tomeasure real and reactive AC power. Moreover, the PER may include abidirectional switch coupled to a secondary side of a distributiontransformer. Additionally or alternatively, the PER may include abidirectional switch coupled to an AC side of a grid. In someembodiments, the PER may include a switched mode power converter coupledto an AC load.

Various embodiments of the present inventive concepts include a methodof operating a PER at or adjacent a premise of a customer of an electricutility. The method may include regulating, via a control input, avoltage of a DC bus of the PER. Moreover, a plurality of switched modepower converters may be coupled to the DC bus and may be configured tointerface with a plurality of DERs, respectively, at the premise of thecustomer.

According to various embodiments, the plurality of DERs may include anenergy storage device at the premise of the customer. The plurality ofswitched mode power converters may include an energy storage switchedmode power converter coupled to the DC bus and to the energy storagedevice. The control input may be a first control input, and the methodmay include providing a second control input to the energy storageswitched mode power converter to insert synthetic inertia for adistribution grid to which the PER is coupled. In some embodiments, theproviding the second control input may include controlling capacitoremulation via the energy storage switched mode power converter to insertthe synthetic inertia.

In various embodiments, the method may include communicating, via afield message bus, between first and second ones of the plurality ofswitched mode power converters. Additionally or alternatively, thecontrol input may include a command to a grid interface switched modepower converter of the PER that is coupled to the DC bus to adjust orhold the voltage of the DC bus. In some embodiments, the command may beprovided in response to a detected AC voltage level. Moreover, the gridinterface switched mode power converter may adjust or hold the voltagewhile operating at a switching frequency of 10 kilohertz or higher.

According to various embodiments, the method may include operating DCmeter circuitry of the PER to measure DC power, and operating AC metercircuitry of the PER to measure real and reactive AC power. Additionallyor alternatively, the control input may be a first control input, andthe method may include providing a second control input to a switch todisconnect the PER from a secondary side of a distribution transformer.

In various embodiments, the control input may be a first control input,and the method may include providing a second control input to a switchto island the PER from an AC side of a grid. Additionally oralternatively, the regulating may include operating a grid interfaceswitched mode power converter of the PER as a voltage source to regulatethe voltage of the DC bus, while the plurality of switched mode powerconverters operates in a current source mode or in a voltage sourcemode.

According to various embodiments, the regulating may include operating agrid interface switched mode power converter of the PER to processcurrent into and out of the DC bus, while an energy storage switchedmode power converter of the plurality of switched mode power convertersoperates as a voltage source to regulate the voltage of the DC bus,Additionally or alternatively, the regulating may include providing acommand to each of the plurality of switched mode power converters tooperate in a voltage droop control mode.

It is noted that aspects of the present inventive concepts describedwith respect to one embodiment may be incorporated in a differentembodiment although not specifically described relative thereto. Thatis, all embodiments and/or features of any embodiment can be combined inany way and/or combination. Applicant(s) reserve(s) the right to changeany originally filed claim or file any new claim accordingly, includingthe right to be able to amend any originally filed claim to depend fromand/or incorporate any feature of any other claim although notoriginally claimed in that manner. These and other objects and/oraspects of the present inventive concepts are explained in detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which form a part of the specification,illustrate various embodiments of the present inventive concepts. Thedrawings and description together serve to fully explain embodiments ofthe present inventive concepts.

FIG. 1A is a schematic illustration of a premise energy router that isat or adjacent a premise of a customer of an electric utility, accordingto various embodiments.

FIG. 1B is a block diagram of a premise energy router, according tovarious embodiments.

FIG. 1C is a block diagram of communications circuitry of a premiseenergy router, according to various embodiments.

FIG. 1D is a block diagram that illustrates details of an exampleprocessor and memory that may be used in accordance with variousembodiments.

FIG. 1E is a block diagram of power electronics circuitry of a premiseenergy router, according to various embodiments.

FIG. 1F is a block diagram of a dynamic Watt-VAR compensator andcontroller (DWVCC), according to various embodiments.

FIG. 1G is a block diagram of power electronics circuitry of a premiseenergy router, according to various embodiments.

FIGS. 2A-2L are flowcharts illustrating operations of a premise energyrouter, according to various embodiments.

DETAILED DESCRIPTION

Various embodiments described herein may provide improved regulation ofa Direct Current (DC) voltage at a DC bus and/or of Alternating Current(AC) power that is injected into or consumed from an AC grid. Suchregulation may be performed at low voltages via a compact apparatus thatis at or adjacent one or more DERs. In some embodiments, a plurality ofthe DERs may be coupled to the same DC bus and may share the sameinverter, which is also coupled to the DC bus. Moreover, someembodiments may provide improved mitigation of harmonics at the AC grid.

Referring now to FIG. 1A, a schematic illustration is provided of apremise energy router PER that is at or adjacent a premise 120 of acustomer of an electric utility, according to various embodiments. Forexample, the customer premise 120 may be a house, apartment, office, orother building, location, or structure, for which an electric utilitymeter could be provided for the customer. A customer premise 120 maythus be a structure such as a billboard, as well as a home or abusiness. Accordingly, the term “premise,” as used herein, may beinterchangeable with the term “premises,” in that either term may beused herein to refer to a building, part of a building, or otherstructure for which an electric utility meter may be provided.

The premise energy router PER may be configured to interface with one ormore distributed energy resources DER at the customer premise 120. Forexample, the premise energy router PER may be configured to interfacewith a solar photovoltaic (PV) system, a fuel cell, an energy storagesystem, or an Electric Vehicle (EV) charging station.

The premise energy router PER may provide electricity from an electricgrid 100 to at least one device or appliance that is at the customerpremise 120, and may measure electricity usage at the customer premise120. For example, at least one appliance may be at the customer premise120 and be powered by the electric grid 100 through the premise energyrouter PER. An appliance may be a refrigerator, dishwasher, laundrymachine, oven, or any other large machine that uses electricity toperform, for example, cooking, cleaning, or food preservation functionsin a household, institutional, commercial, or industrial setting.

Additionally or alternatively to appliances, various devices that useelectricity may be at the customer premise 120 and may be connected tothe premise energy router PER. For example, consumer electronics andheating/cooling devices and/or systems may be at the customer premise120. Moreover, in some embodiments, the customer premise 120 may be abillboard, and the electric grid 100 may provide power for lights or anelectronic display of the billboard.

The premise energy router PER is downstream from an electric utilitysubstation 140 that serves the customer premise 120. The substation 140may include one or more transformers. Between the substation 140 and thepremise energy router PER is a distribution transformer DT, which maycontrol a voltage level of power that is transmitted to the premiseenergy router PER. In particular, the distribution transformer DT servesthe customer premise 120 and may be the closest transformer of theelectric grid 100 to the customer premise 120. The distributiontransformer DT may be underground, mounted on a concrete pad, mounted ona utility pole, or otherwise fixed at a location that is upstream andspaced apart from the premise energy router PER.

A single distribution transformer DT may provide power to one or morecustomers in a given area. For example, in an urban area, a plurality ofhomes may be fed off of a single distribution transformer DT. Ruraldistribution, on the other hand, may use one distribution transformer DTper customer. Moreover, a large commercial or industrial complex mayrely on multiple distribution transformers DT.

A distribution transformer DT has a low-voltage secondary (e.g., output)side that distributes power to one or more customers. For example, inthe United States, the low-voltage secondary side of the distributiontransformer DT may be configured for a 240/120-Volt system, and threewires (including one neutral wire) may be fed from the low-voltagesecondary side to the premise energy router PER.

Referring now to FIG. 1B, a block diagram is provided of a premiseenergy router PER, according to various embodiments. A low-voltagesecondary service connection 107 of the distribution transformer DT isinput to the premise energy router PER. Although the low-voltagesecondary service connection 107 is illustrated as a single wire forconvenience, the inventive entity appreciates that three wires(including one neutral wire) may be used. In some embodiments, thelow-voltage secondary service connection 107 may be configured for a240/120-Volt system, and may be input to electric utility metercircuitry 101 of the premise energy router PER. Moreover, in someembodiments, the customer premise 120 may be a commercial or industrialcustomer premise, and the low-voltage secondary service connection 107may use a higher voltage than 240 Volts (e.g., 277/480 Volts, forcommercial/industrial applications). Accordingly, although the premiseenergy router PER may be a single-phase device for residentialapplications, the inventive entity appreciates that the premise energyrouter PER may optionally be used at higher voltages than 120/240 Voltsfor three-phase applications. Moreover, in some embodiments, the premiseenergy router PER may use split-phase voltages.

The electric utility meter circuitry 101 of the premise energy routerPER includes hardware and/or software configured to perform thefunctionality of an electric utility meter. Accordingly, the premiseenergy router PER may replace an electric utility meter. As an example,the customer premise 120 may be a house of a customer, and the premiseenergy router PER may be mounted on the side of the house to replace anelectric utility meter that had been mounted on the side of the house.The electric utility meter circuitry 101 of the premise energy routerPER may thus be configured to measure electricity usage (e.g., tomeasure AC and/or DC usage in kilowatt-hours (kWh)) by the customer atthe customer premise 120. In particular, the usage measured may be usageof electricity that is supplied by a specific electric utility (e.g.,the electric utility that owns the premise energy router PER) to thecustomer premise 120.

As the premise energy router PER may be an utility-owned device ratherthan a customer-owned device, it may be separate from a breaker box/loadcenter and may provide more access/control to the electric utility thatowns it than would a customer-owned device. In some embodiments,however, the premise energy router PER may optionally be used as acircuit breaker. Moreover, the premise energy router PER, which may beon the outside of a customer's home, may be separate from coaxial linesto the home. Additionally or alternatively, the premise energy routerPER may be used as a PV inverter and/or a battery charger, and may thusreplace an existing PV inverter or battery charger at the customerpremise 120. In some embodiments, when the premise energy router PER isoperating in an inverter mode for PVs, a user may change the mode ofoperation (e.g., among modes such as maximum generation limit function,fixed power factor, intelligent Volt-VAR function, Volt-Watt function,frequency-Watt function, etc.).

Referring still to FIG. 1B, the premise energy router PER includes powerelectronics circuitry 102 and communications circuitry 103. For example,the power electronics circuitry 102 may use 120/240 Volts provided fromthe distribution transformer DT by the low-voltage secondary serviceconnection 107. In particular, the power electronics circuitry 102 maybe low-voltage power electronics circuitry that uses 600 Volts or lower,including 120/240 Volts (as well as 208, 277, 480, or 600 Volts, forexample). The inventive entity appreciates that the voltage regulatedmay be AC and/or DC. Moreover, in some embodiments, the electric utilitymeter circuitry 101 may be referred to as meter metrology, and theelectric utility meter circuitry 101 and/or the power electronicscircuitry 102 may be configured to measure phasor measurement unitsand/or voltage levels, to perform waveform pattern recognition, tomonitor AC and DC load behavior, to perform condition-based maintenanceand risk assessment of assets, and/or to provide time-synchronizationfunctionality. For example, the electric utility meter circuitry 101and/or the power electronics circuitry 102 may be configured to providea synchrophasor that measures high order harmonics, provides a cleanwaveform, and/or re-synchronizes to an AC line. Additionally oralternatively, the power electronics circuitry 102 may be configured toregulate gain, power factor, voltage harmonic levels, and currentharmonic levels, and/or to provide a DC power source. For example, thepower electronics circuitry 102 may be configured to cancel current andvoltage harmonics, and/or to balance phases.

In one example, the power electronics circuitry 102 may be configured toregulate a voltage level of 600 Volts or lower that is provided to thecustomer premise 120 via a connection 104. For embodiments in which thecustomer premise 120 is a home of the customer, the load at theconnection 104 may be between 0 Volt-Amperes and 15,000 Volt-Amperes.Accordingly, the electric utility meter circuitry 101 may, in someembodiments, be configured to operate with a load from the customerpremise 120 of between 0 Volt-Amperes and 15,000 Volt-Amperes. In otherwords, the power rating for the premise energy router PER may range from0 Volt-Amperes to 15,000 Volt-Amperes. In some higher-power embodiments(e.g., three-phase applications), however, the range may extend above15,000 Volt-Amperes. Also, the load current may be sinusoidal, 60 Hertz.In general, in comparison with the premise energy router PER, thesubstation 140 and the distribution transformer DT may handle muchlarger loads (e.g., 50,000 Volt-Amperes or higher).

Moreover, in some embodiments, the power electronics circuitry 102 mayinclude a DC bus 112, which may also be referred to as a DC port. The DCbus 112 may be configured to provide a DC power source to the customerpremise 120. For example, the DC bus 112 may be a 400-Volt DC bus. Asanother example, the DC bus 112 may be a 1,000-Volt DC bus. Theinventive entity appreciates, however, that the DC bus 112 may provide aDC voltage output anywhere in the range of 24-2,000 Volts. In someembodiments, the power electronics circuitry 102 may include poweroutput circuitry connected to the DC bus 112 and configured to convert aDC output of a PV solar panel into a utility frequency AC that can befed into a commercial electrical grid (e.g., the electric grid 100) orused by a local, off-grid electrical network. The inventive entityappreciates that the DC bus 112 may optionally provide a plurality of DCports (e.g., a plurality of DC ports providing different DC voltagelevels). In other words, although FIG. 1B illustrates one DC bus 112, aplurality of DC buses 112 may optionally be included in the premiseenergy router PER. Moreover, the inventive entity appreciates that theDC bus 112 may include a plurality of stages, including an AC/DC stage,a DC/DC stage, and/or a DC/AC stage.

Additionally or alternatively, the power electronics circuitry 102 maybe configured to convert AC power received from the low-voltagesecondary service connection 107 into DC power and to provide the DCpower to one or more DC devices via the DC bus 112. In some embodiments,the power electronics circuitry 102 may include circuitry configured toprovide both (i) AC-to-DC rectifier functionality (e.g., for convertingAC into DC and providing DC from the DC bus 112 to a DC load) and (ii)DC-to-AC inverter functionality (e.g., for converting DC from a solardevice or a battery storage into AC). Moreover, in some embodiments, thepower electronics circuitry 102 of the premise energy router PER mayinclude a DC-to-DC converter (or a plurality of DC-to-DC converters)that reduces the 400 Volts to a lower DC voltage level that can beprovided into the customer's home. The DC-to-DC converter may havelevel-shift capability and/or may be a buck-boost converter.Additionally or alternatively, hardware of the power electronicscircuitry 102 that performs inverter functionality may be configured toprovide voltage and/or current source modes, and/or to provide either anisolated power supply or a non-isolated power supply.

The premise energy router PER may also include one or more switches S,which may help to reduce the impact to a customer of a problem with thepower electronics circuitry 102 or of a problem with the electric grid100. For example, the power electronics circuitry 102 may sense an openneutral situation (or any other power anomaly/error) and responsivelytrigger a switch S. In some embodiments, a switch S may keep thecustomer from losing power. The components of the premise energy routerPER that are illustrated in FIG. 1B may each be internal to a housing106 (e.g., a metal and/or plastic housing) of the premise energy routerPER. Accordingly, the components of the premise energy router PER may beat the same location, in the same physical box/unit.

Referring now to FIG. 1C, a block diagram is provided of thecommunications circuitry 103 of the premise energy router PER of FIGS.1A and 1B, according to various embodiments. The communicationscircuitry 103 may include a processor 150, a network interface 160, anda memory 170. The processor 150 may be coupled to the network interface160. The processor 150 may be configured to communicate with devices(e.g., communication nodes) at the customer premise 120, at thesubstation 140, and/or at an electric utility data center via thenetwork interface 160. Additionally or alternatively, the processor 150may control communications between different components of the powerelectronics circuitry 102. Such communications may be coordinated by afield message bus. For example, the following patent applications, theentire disclosures of which are hereby incorporated by reference,discuss a field message bus: U.S. patent application Ser. No.14/264,757, filed on Apr. 29, 2014, and published as U.S. PatentApplication Publication No. 2015/0097694, entitled Methods of ProcessingData Corresponding to a Device that Corresponds to a Gas, Water, orElectric Grid, and Related Devices and Computer Program Products, andU.S. patent application Ser. No. 14/270,914, filed on May 6, 2014, nowU.S. Pat. No. 9,722,665, entitled Communication Nodes and Sensor DevicesConfigured to Use Power Line Communication Signals, and Related Methodsof Operation.

The network interface 160 may include, for example, one or more wirelessinterfaces 161 (e.g., 3G/LTE, other cellular, WiFi, Global PositioningSystem (GPS) interfaces, etc.) and one or more physical interfaces 162(e.g., Ethernet, serial, USB interfaces, etc.). Moreover, the networkinterface 160 may optionally include one or more power line interfaces163 (e.g., Low Voltage (LV) or Mid Voltage (MV) PLC).

Accordingly, the premise energy router PER may, in some embodiments,have multiple integrated communications options. For example, thepremise energy router PER may provide PLC, WiFi, Zigbee, Z-wavecommunications, or other communications via the network interface 160into the customer premise 120 (e.g., a customer's home), and may providecellular communications or other communications to the electric grid100. As an example, the premise energy router PER may communicate withsmart appliances and demand response devices (e.g., devices that reduceload by turning off appliances, air conditioning, etc.) at the customerpremise 120. By sharing data from inside the customer premise 120 withthe premise energy router PER, the customer can improve the efficiencyof power delivery by the premise energy router PER. In some embodiments,the premise energy router PER may optionally be used to control smartdevices at the customer premise 120, and may thus reduce the totalenergy consumption at the customer premise 120.

Moreover, the premise energy router PER may have a modular design thatallows the premise energy router PER to use a variety of communicationstechnologies, and to therefore not be limited exclusively to onecommunications technology, such as PLC communications. The premiseenergy router PER may be referred to as having a modular design becausethe meter circuitry 101, the power electronics circuitry 102, and/or thecommunications circuitry 103 may be integrated circuits provided onrespective plug-and-play cards that can be easily added to and removedfrom (e.g., removed and replaced with a new and/or different cardproviding improved/different functionality). As an example, thecommunications circuitry 103 may include a PLC card that may be replacedwith or supplemented by a card that provides WiFi communications.Various other types of cards may also be used, including voltageinverter/rectifier cards, among other types of cards that aremodular/interchangeable from one premise energy router PER to the next.

Referring still to FIG. 1C, the memory 170 may be coupled to theprocessor 150. The memory 170 may also store instructions/algorithmsused by the processor 150. For example, the memory 170 of the premiseenergy router PER may include one or more algorithms thatimprove/optimize power flow to the customer premise 120. Using suchalgorithms, the premise energy router PER may maintain a datalog/history for the meter circuitry 101, the power electronics circuitry102, and/or the communications circuitry 103. Moreover, the premiseenergy router PER may use such algorithms to enable an override ofpredetermined set points, such as to enable an override of a 120/240Volt set point to thereby reduce the output voltage below 120/240 Volts.Additionally or alternatively, the premise energy router PER may usesuch algorithms to provide notification of power/communications errorsand notification of use of a switch S.

The communications circuitry 103 may include core hardware componentssuch as a power supply, 10 MHz or higher speed processor(s), and 1Megabyte (MB) or more of RAM. Because a premise energy router PERincludes integrated processor 150 and memory 170 capability, the premiseenergy router PER can move/adjust voltage levels, VARs, etc. Theintegrated processor 150 and memory 170 capability may be referred to asan integrated distributed intelligence platform. Although the processor150 is illustrated as being part of the communications circuitry 103,the premise energy router PER may include one or more processors 150that are outside of the communications circuitry 103. For example, themeter circuitry 101 and/or the power electronics circuitry 102 mayoperate under the control of one or more processors 150 that is/areinside the housing 106 of the premise energy router PER but notnecessarily inside the communications circuitry 103.

The communications circuitry 103 may include core applications, such asCPU/memory/OS management applications, port/device drivers,router/Internet Protocol (IP) services, network management services,basic protocol support, SCADA, custom Application Programming Interface(API)/applications, and device security services. Moreover, thecommunications circuitry 103 may include virtual applications, such as avirtual machine (e.g., a Java Virtual Machine), message bus(es), messagebroker(s), protocol adapters, mini-SCADA, open-standards API, andthird-party applications (e.g., security/analytics applications). Forexample, the communications circuitry 103 may support DistributedNetwork Protocol (DNP) (e.g., DNP 3.0), Modbus, and Message QueueTelemetry Transport (MQTT) protocols. The core applications may use suchsoftware as C++/Linux, and the virtual applications may use suchsoftware as Java/Linux.

Referring now to FIG. 1D, a block diagram is provided that illustratesdetails of an example processor 150 and memory 170 of the communicationscircuitry 103 that may be used in accordance with various embodiments.The processor 150 communicates with the memory 170 via an address/databus 180. The processor 150 may be, for example, a commercially availableor custom microprocessor. Moreover, the processor 150 may includemultiple processors. The memory 170 is representative of the overallhierarchy of memory devices containing the software and data used toimplement various functions of the communications circuitry 103 or othercircuitry of the premise energy router PER as described herein. Thememory 170 may include, but is not limited to, the following types ofdevices: cache, ROM, PROM, EPROM, EEPROM, flash, Static RAM (SRAM), andDynamic RAM (DRAM).

As shown in FIG. 1D, the memory 170 may hold various categories ofsoftware and data, such as an operating system 173. The operating system173 controls operations of the communications circuitry 103 or othercircuitry of the premise energy router PER, such as the powerelectronics circuitry 102. In particular, the operating system 173 maymanage the resources of the communications circuitry 103 or othercircuitry of the premise energy router PER and may coordinate executionof various programs by the processor 150.

Referring now to FIG. 1E, a block diagram is provided that illustratesdetails of power electronics circuitry 102 of the premise energy routerPER. In addition to the DC bus 112, the power electronics circuitry 102may include a grid interface power converter 122 that is coupled to theDC bus 112 and to an AC bus. The AC bus is illustrated in FIG. 1E by anAC Point of Common Coupling (PCC) that is between the premise energyrouter PER and a distribution transformer DT. For embodiments in whichthe customer premise 120 is a residential premise, a voltage of the ACbus may be between about 120 Volts and about 240 Volts. For example, thevoltage of the AC bus may be 120 Volts, 208 Volts, or 240 Volts.

The grid interface power converter 122 may be configured to regulate avoltage of the DC bus 112. The voltage, which the grid interface powerconverter 122 may be configured to adjust or to hold constant, may bebetween about 24 Volts and about 2,000 Volts. For example, when thecustomer premise 120 is a residential premise, the DC voltage at the DCbus 112 may be 100-600 Volts. In another example, the DC voltage at theDC bus 112 may be 500-1,500 Volts. Moreover, the grid interface powerconverter 122 may be a switched mode power converter and may have aswitching frequency of 10 kilohertz or higher.

The power electronics circuitry 102 may also include one or more DERpower converters 132 that are coupled to the DC bus 112. Each DER powerconverter 132 may be a DC-to-DC power converter that is configured tointerface with a respective distributed energy resource DER that is atthe customer premise 120. Generally speaking, a DC-to-DC power converterfacilitates power flow between two different/disparate DC voltagelevels. Like the grid interface power converter 122, each DER powerconverter 132 may be a switched mode power converter having a switchingfrequency of 10 kilohertz or higher.

Referring now to FIG. 1F, the grid interface power converter 122, whichis coupled to the DC bus 112 and to the AC bus, may include circuitrythat is configured to operate in either a power inverter mode or a powerrectifier mode, depending on the direction of power flow. In particular,the grid interface power converter 122 may be configured to operate inthe power inverter mode when it receives DC power, and in the powerrectifier mode when it receives AC power. The power inverter mode andthe power rectifier mode may be controlled by one or more processors 150coupled to, or included in, the grid interface power converter 122. Theprocessor(s) 150 may be either internal or external to the powerelectronics circuitry 102. The combination of the processor(s) 150, thegrid interface power converter 122, and the DER power converter(s) 132may be referred to herein as a DWVCC 122′. Moreover, the grid interfacepower converter 122 and the DER power converter(s) 132, either with orwithout the processor(s) 150, may be referred to herein as a“compensator” or a “dynamic Watt-VAR compensator.” In some embodiments,the AC PCC, which is the point on the AC grid 100 to which the DWVCC122′ is connected, may be outside of the housing 106 of the premiseenergy router PER, whereas the DC bus 112 may be inside the housing 106.

When operating in the power inverter mode, the grid interface powerconverter 122 can use the DC voltage at the DC bus 112 to provide any ACoutput, without using an AC transformer. For example, software controlvia the processor(s) 150, including software-definable AC voltagelevels, of the DC bus 112 may eliminate the need for an AC transformer.Accordingly, regardless of whether the DC voltage at the DC bus 112 is24 Volts or 2,000 Volts, the power inverter mode of the grid interfacepower converter 122 can output a desired AC voltage, such as 120 Volts,240 Volts, or 480 Volts. Moreover, the grid interface power converter122 may be single-phase, split-phase, or three-phase circuitry, and maybe referred to herein as a “bidirectional power converter” because itmay be configured to operate both as an AC-to-DC rectifier and as aDC-to-AC inverter. Accordingly, in some embodiments, the hardware of thegrid interface power converter 122 may be referred to herein as“bidirectional inverter-rectifier circuitry,” which is configured toperform both inverter and rectifier functionality (e.g., configured toselectively perform one of the two functionalities in response to thedirection of power flow).

Referring now to FIG. 1G, a block diagram is provided that illustrates afurther detailed example of the power electronics circuitry 102 of FIG.1E. As illustrated in this example, the DC bus 112 may be a shared DCbus that is coupled to a plurality of the distributed energy resourcesDERs via their respective DER power converters 132. In particular, FIG.1G illustrates a first DER power converter 132-1 that is coupled to afirst distributed energy resource DER-1, and a second DER powerconverter 132-2 that is coupled to a second distributed energy resourceDER-2.

The distributed energy resources DER-1 and DER-2 may (i) both be DCpower generation elements, (ii) both be DC energy storage elements, or(iii) be a DC power generation element and a DC energy storage element,respectively. Accordingly, the distributed energy resources DER-1 andDER-2 may be referred to herein as a plurality of “DC power generationand/or DC energy storage elements.” Examples of DC power generationelements include a solar PV device/system, a fuel cell, and a DCgenerator. Moreover, examples of DC energy storage elements include abattery device/system, a fast DC EV charger (e.g., a Level 3 charger), asuper/ultra-capacitor, and a flywheel.

The shared DC bus 112 may be configured to receive DC power from thedistributed energy resources DER-1 and DER-2. For example, the firstdistributed energy resource DER-1 may be a DC power generation elementsuch as a solar PV system or a fuel cell, and the second distributedenergy resource DER-2 may be a DC energy storage element such as abattery or a capacitor. Moreover, the grid interface power converter 122may be configured to convert, using the power inverter mode, this DCpower into AC power. The grid interface power converter 122, whenoperating in the power inverter mode, may be further configured toinject current to the AC PCC, which may be a PCC that is between (a) theAC grid 100 to which the premise energy router PER is coupled and (b) aload (e.g., an AC load A) of the customer premise 120. Accordingly, thegrid interface power converter 122 can inject current into the AC grid100. For example, the grid interface power converter 122 can injectcurrent to serve both (a) the AC grid 100 and (b) the load of thecustomer premise 120, as excess current can go to the AC grid 100 whenthe grid interface power converter 122 injects more current than theload can handle. The injected current may include a combination ofdirect harmonic current and quadrature current. As an example, theinjected current may include a combination of (i) direct fundamental andharmonic current and (ii) quadrature fundamental and harmonic current.

Because the premise energy router PER includes the grid interface powerconverter 122 that is configured to operate in the power inverter mode,the premise energy router PER does not need to rely on, and thus may befree of, any step-up or step-up down AC transformer. Moreover, when thegrid interface power converter 122 is coupled to the shared DC bus 112of both (i) a solar PV and (ii) a battery, the grid interface powerconverter 122 operating in the power inverter mode may providesignificant supply capacity. An inverter that is only coupled to acapacitor, on the other hand, may not provide much supply capacity, asit may be limited to leveraging VARs from the capacitor. Also, in theexample of the solar PV and the battery, the grid interface powerconverter 122 may regulate power flow from the solar PV into the grid100 via the DC bus 112 or into the battery via the DC bus 112.Furthermore, by using the common/shared grid interface power converter122 including the power inverter mode for all DC generation and storageelements, the use of different respective inverters for the DCgeneration and storage elements can be avoided.

The premise energy router PER may also be free of any mechanical circuitbreaker, as the grid interface power converter 122 may include one ormore power semiconductor devices 122S that are configured to switch at afrequency of 10 kilohertz or higher. The power semiconductor devices122S are high-speed bidirectional devices that may perform the functionsof high-speed relays and may mitigate fault conditions in the gridinterface power converter 122 and a DC-to-DC converter coupled thereto.Aside from these bidirectional semiconductor devices, the premise energyrouter PER may not use any other current interruption and isolationdevice, such as AC or DC circuit breakers. In some embodiments, abidirectional semiconductor device may be provided by a combination oftwo unidirectional semiconductor devices. The grid interface powerconverter 122 (e.g., the inverter mode thereof) may also providesufficient isolation that no auxiliary transformer may be needed betweenthe grid interface power converter 122 and the grid 100 for galvanicisolation.

The example of FIG. 1G also illustrates a DC link capacitor 114 that iscoupled to the DC bus 112 and to the second distributed energy resourceDER-2. For example, the DC link capacitor 114 may be used when thesecond distributed energy resource DER-2 is a battery energy storagesystem/device. As an alternative to the DC link capacitor 114, a bank ofcapacitors may be coupled between the DC bus 112 and the battery energystorage system/device.

When the second distributed energy resource DER-2 is an energy storagesystem/device, such as a battery or an ultracapacitor, the DER powerconverter 132-2 coupled thereto may be configured to insert syntheticinertia into the electric grid 100. In particular, the DER powerconverter 132-2 may insert synthetic inertia into a distribution portion(e.g., a 480 Volts AC or lower portion) of the electric grid 100, whichportion may be referred to herein as a “distribution grid.” Thesynthetic inertia is provided by the combined operation of (a) theinverter mode of the grid interface power converter 122 and (b) the DERpower converter 132-2, which is a DC-to-DC converter that emulates ahigh value of capacitance. Moreover, this DER power converter 132-2 maybe referred to herein as an “energy storage power converter,” an “energystorage DC-to-DC converter,” or, when it has switched modefunctionality, an “energy storage switched mode power converter.” Insome embodiments, a battery that is coupled to the DER power converter132-2 may include a battery management system that may communicate withthe DER power converter 132-2.

The DER power converters 132-1 and 132-2 may communicate with eachother, and/or with the grid interface power converter 122, via a fieldmessage bus. Such field message bus communications may control the powerconverters 122, 132 in a coordinated manner. For example, thecommunications circuitry 103 may be coupled to the power electronicscircuitry 102 and may be configured to provide communications, via thefield message bus, between components of the power electronics circuitry102 such as the DER power converters 132-1 and 132-2. As an example, thefield message bus may coordinate communications, via the communicationscircuitry 103, between the grid interface power converter 122, a solarPV power converter, and a battery power converter.

The meter circuitry 101 of the premise energy router PER may include ACmeter circuitry 101-A that is configured to measure real and reactive ACpower, and DC meter circuitry 101-D that is configured to measure DCpower. The AC meter circuitry 101-A and the DC meter circuitry 101-D maybe coupled to power-flow paths of various components of the powerelectronics circuitry 102. For example, the DER power converters 132-1and 132-2 may have DC meter circuitry 101-D coupled thereto. As anotherexample, the power electronics circuitry 102 may include a motor drive153 having DC meter circuitry 101-D coupled thereto. Although this DCmeter circuitry 101-D is illustrated as coupled to an output of themotor drive 153 that is inside the power electronics circuitry 102, itwill be understood that the DC meter circuitry 101-D itself may beoutside of the power electronics circuitry 102, as indicated by brokenline in FIG. 1G. The motor drive 153 may include one or more electricmotor drives, such as AC variable frequency drives (VFD) and brushlessDC (BLDC) motor drives with regenerative braking/stop capability.

For simplicity of illustration, a few examples of the DC meter circuitry101-D are illustrated in FIG. 1G. It will be understood, however, thatvarious sensors (e.g., voltage and/or current sensors) inside thehousing 106 of the premise energy router PER may be coupled to variouscomponents of the power electronics circuitry 102 to measure DC power.

Similarly, although FIG. 1G illustrates an example of the AC metercircuitry 101-A that is coupled to a node/location between an islandingswitch S_(ISLAND) and a disconnect switch S_(DISCONNECT) to measure howmuch AC power is supplied to an AC load A, it will be understood thatvarious sensors inside the housing 106 may be coupled to variouscomponents inside or outside of the power electronics circuitry 102 tomeasure real and reactive AC power. For example, AC meter circuitry101-A may be coupled to a path of power flow between the grid interfacepower converter 112 and an AC EV charger power converter 142. As anotherexample, the motor drive 153 may be coupled to an electric machine 154that is at the customer premise 120, and the motor drive 153 and theelectric machine 154 may have AC meter circuitry 101-A therebetween. Insome embodiments, the electric machine 154 may include diagnostics thatcommunicate with the motor drive 153. Examples of the electric machine154 include an induction motor, a synchronous motor, and a brushless DCmotor. Moreover, AC meter circuitry 101-A may be coupled to a path ofpower flow between the AC PCC and the islanding switch S_(ISLAND) of thepremise energy router PER.

As with the DC meter circuitry 101-D, it will be understood that the ACmeter circuitry 101-A may be outside of, yet coupled to, the powerelectronics circuitry 102, as indicated by broken line in FIG. 1G. Allof the AC meter circuitry 101-A and DC meter circuitry 101-D may beinside the housing 106 of the premise energy router PER.

The islanding switch S_(ISLAND) may be a bidirectional switch that iscoupled to an AC side of the grid 100. Moreover, the islanding switchS_(ISLAND) may be one among a plurality of switches S (FIG. 1B) that areinside the housing 106 of the premise energy router PER. For example,the premise energy router PER may further include the disconnect switchS_(DISCONNECT), which may be a bidirectional switch that is coupled tothe secondary side of the distribution transformer DT. As an example,the disconnect switch S_(DISCONNECT) may be coupled to a low-voltagesecondary service connection 107 (FIG. 1B). Although the disconnectswitch S_(DISCONNECT) is also coupled downstream to components among thepower electronics circuitry 102, it will be understood that theislanding switch S_(ISLAND) and the disconnect switch S_(DISCONNECT) maythemselves be outside of the power electronics circuitry 102.

The AC load A may be coupled to a node/location between the islandingswitch S_(ISLAND) and the disconnect switch S_(DISCONNECT), which is aprotection mechanism to keep the AC load A supplied by the AC grid 100.Accordingly, the disconnect switch S_(DISCONNECT) does not disconnectthe AC load A, which is the aggregate AC load of the customer premise120 and thus may be, for example, a residential load including a house,air conditioner, washer/dryer, etc. Rather, the AC load A remainsconnected to the distribution transformer DT via the islanding switchS_(ISLAND), which can island the AC load and every component that isdownstream from the disconnect switch S_(DISCONNECT). The disconnectswitch S_(DISCONNECT) can, however, disconnect an AC EV charging station143 that is at the customer premise 120 from the premise energy routerPER. The AC EV charging station 143, which may be a Level 1 or Level 2EV charging station, is coupled to the AC EV charger power converter142. The disconnect switch S_(DISCONNECT) also disconnects the gridinterface power converter 122 from the distribution transformer DT.

Referring now to FIGS. 2A-2L, flowcharts are provided illustratingoperations of an apparatus, such as a premise energy router PER,according to various embodiments. The operations may be performed whilethe apparatus (e.g., the premise energy router PER) is connected betweena utility secondary service 107 (FIG. 1B) of an electric utility and awiring connection 104 (FIG. 1B) of a customer at a premise 120 (FIG. 1A)of the customer. For example, the operations of FIGS. 2A-2L may beperformed while the apparatus is downstream from a substation 140 (FIG.1A) that serves the premise 120 and without using any step-up orstep-down AC transformer in the apparatus. As an example, the operationsof FIGS. 2A-2L may be performed while the apparatus is at or adjacent(e.g., within about 300 feet of) a residential premise of the customer.

As shown in FIG. 2A, the operations may include measuring (Block 210),using AC meter circuitry 101-A and/or DC meter circuitry 101-D of theelectric utility meter circuitry 101 of the apparatus, usage ofelectricity supplied by the electric utility to the premise 120 of thecustomer. As an example, the operation(s) of Block 210 may includeperforming measurements in kilowatt hours or in other units ofmeasurement of energy used. The operation(s) of Block 210 may measure anaggregate (e.g., overall) power consumption at the customer premise 120.In some embodiments, the aggregate power consumption may be the totalpower consumed by the AC load A, as measured by the AC meter circuitry101-A that is coupled to the AC load A. Alternatively, the aggregatepower consumption may be the total power consumption measured by eachinstance of AC meter circuitry 101-A and DC meter circuitry 101-D in thepremise energy router PER. Also, in some embodiments, the powerelectronics circuitry 102 may be unmetered so that it does not affect acustomer's energy consumption. For example, the premise energy routerPER may include an AC bus bar (FIG. 1B) that is independently connectedbetween the utility secondary service 107 of the electric utility andeach of the electric utility meter circuitry 101 and the powerelectronics circuitry 102.

FIG. 2A further illustrates that the operations may include regulating(Block 220), using a grid interface power converter 122 of the DWVCC122′ (FIG. 1F) of the apparatus, a voltage of a DC bus 112 in theapparatus. Although Block 220 is illustrated as occurring after Block210, it will be understood that the operation(s) of Block 220 mayadditionally or alternatively be performed during and/or before theoperation(s) of Block 210.

Moreover, as shown in FIG. 2B, the measuring (Block 210) operation(s)may, in some embodiments, be omitted or performed independently of theregulating (Block 220) operation(s). Also, Block 220′ of FIG. 2Billustrates that the regulating (Block 220) operation(s) may beperformed in response to a control input. For example, a processor 150may provide a control input to the grid interface power converter 122 toregulate the voltage of the DC bus 112.

Furthermore, referring again to FIG. 1G, the apparatus that performs theoperation(s) of Block 220′ of FIG. 2B may include DER power converters132-1, 132-2 that share the DC bus 112 and are configured to interfacewith respective distributed energy resources DER-1, DER-2. For example,the operation(s) of Block 220′ may include operating the power invertermode of the grid interface power converter 122 that is coupled to theshared DC bus 112 and is shared by the distributed energy resourcesDER-1, DER-2. Additionally or alternatively, the operation(s) of Block220′ may include operating a power rectifier mode of the grid interfacepower converter 122 that is coupled to the shared DC bus 112 and isshared by the distributed energy resources DER-1, DER-2. The sharedrectifier mode may help to improve supply.

Referring now to FIG. 2C, operations of the apparatus may includeinserting synthetic inertia to the grid 100. Any energy storage device,such as a capacitor or a battery, can support synthetic inertia. Whenthe distributed energy resource DER-2 is an energy storage device, theDER power converter 132-2 coupled thereto may be referred to herein asan “energy storage power converter” or, when it provides switched modefunctionality, as an “energy storage switched mode power converter.” Inaddition to the control input that is provided in Block 220′, operationsof the apparatus may include providing (Block 230) a further (e.g.,second) control input to the energy storage power converter 132-2 toinsert synthetic inertia to a distribution portion of the grid 100. Forexample, the control input (e.g., from a processor 150) of Block 230 maycontrol capacitor emulation via the energy storage power converter 132-2to insert the synthetic inertia.

Referring now to FIG. 2D, operations of the apparatus may includecommunicating (Block 240), via a field message bus, between the DERpower converters 132-1 and 132-2. Additionally or alternatively, thecommunicating (Block 240) may be performed between the grid interfacepower converter 122 and one or both of the DER power converters 132-1and 132-2. In some embodiments, the communicating (Block 240) may beperformed via the communications circuitry 103. Moreover, although shownin FIG. 2D, the communicating (Block 240) may be performed in any ofFIGS. 2A-2L, and may be performed before, during, and/or after theregulating (Block 220/220′) operation(s). In some embodiments, thecommunicating (Block 240) may include transmitting software controlsand/or configuration settings via the field message bus.

Referring now to FIG. 2E, the regulating operation(s) of Block 220′ mayinclude operating the grid interface power converter 122 of theapparatus to adjust or hold (Block 220″) the voltage of the DC bus 112.For example, the control input of Block 220′ may include a command tothe grid interface power converter 122 to adjust or hold the voltage ofthe DC bus 112. As an example, the command may be provided in responseto an AC voltage level that is detected (Block 215) by the apparatus. Inparticular, upon detecting an AC voltage change, it may be desirable toadjust the DC voltage accordingly. Moreover, in some embodiments, theadjusting or holding (Block 220″) may be performed by the grid interfacepower converter 122 while operating at a switching frequency of 10kilohertz or higher.

Referring now to FIG. 2F, operations of the apparatus may includeperforming AC and/or DC power measurements (Block 250), using AC metercircuitry 101-A and/or DC meter circuitry 101-D of the utility metercircuitry 101. For example, the power measurement(s) of Block 250 mayinclude operating DC meter circuitry 101-D (FIG. 1G) of the apparatus tomeasure DC power, as well as operating AC meter circuitry 101-A (FIG.1G) of the apparatus to measure real and reactive AC power. Suchmeasurement(s) may be performed at one or more individual nodes in FIG.1G. As an example, the measurement(s) may be performed by the AC metercircuitry 101-A that is coupled to the AC EV power converter 142, whileomitting measurement(s) at one or more other nodes in FIG. 1G. In someembodiments, the operation(s) of Block 250 may be combined with themeasuring operation(s) of Block 210 (FIG. 2A). For example, theoperation(s) of Block 250 may include measuring total power consumptionby the AC load A and/or measuring power consumption at each measurednode in FIG. 1G, to provide the aggregate measurement of Block 210.

Referring now to FIG. 2G, operations of the apparatus may includeproviding (Block 225) a further (e.g., second) control input to thedisconnect switch S_(DISCONNECT) to disconnect the apparatus from thesecondary side of the distribution transformer DT. For example, aprocessor 150 may provide this control input in response to detecting(Block 224) a problem with the apparatus. As an example, in the event ofan issue (e.g., a fault) with the premise energy router PER, such as anissue with the power electronics circuitry 102, the disconnect switchS_(DISCONNECT) may trip off the premise energy router PER, which mayprotect the customer from losing power at the premise 120.

Referring now to FIG. 2H, in addition to, or as an alternative to, theoperations of Blocks 224 and 225, the operations of the apparatus mayinclude providing (Block 227) a further (e.g., second or third) controlinput to the islanding switch S_(ISLAND) to island the apparatus fromthe AC side of the grid 100. For example, a processor 150 may providethis control input in response to detecting (Block 226) an outage of thegrid 100. Accordingly, the islanding switch S_(ISLAND) can isolate thecustomer in the event of a grid outage.

The switches S_(DISCONNECT) and S_(ISLAND) may be bidirectionalswitches, which may be controlled by any microcontroller, such as aprocessor 150, that controls one or more of the power converters 122,132, 142. Unlike switched mode power converters, which may include thepower semiconductor devices 122S, however, the switches S_(DISCONNECT)and S_(ISLAND) may not operate at 10 kilohertz (or higher) on an ongoingbasis. It will be understood that any of the power converters 122, 132,and 142 may include at least one power semiconductor device 122S thatoperates at a switching frequency of 10 kilohertz or higher.

Referring now to FIG. 2I, the regulating operation(s) of Block 220/220′may include operating (Block 220VS) the grid interface power converter122 as a voltage source to regulate the voltage of the DC bus 112. Whilethe grid interface power converter 122 is operating (Block 220VS) as avoltage source, the DER power converters 132 may operate in a currentsource mode or in a voltage source mode. For example, all powerconverters 122, 132, 142 can concurrently operate as a voltage source.Moreover, operations of the premise energy router PER may includedynamically selecting (e.g., via the processor(s) 150) whether one ormore of the power converters 122, 132, 142 operates as a voltage source.

Referring now to FIG. 2J, the regulating operation(s) of Block 220/220′may include operating (Block 220P) the grid interface power converter122 to process current into and out of the DC bus 112, while an energystorage power converter (e.g., the DER power converter 132-2) operatesas a voltage source to regulate the voltage of the DC bus 112.

Referring now to FIG. 2K, the regulating operation(s) of Block 220/220′may include providing (Block 220VD) a command to each of the powerconverters 122 and 132 to operate in a voltage droop control mode, whichmay improve system stability. As an example, one or more processors 150may provide this command to the power converters 122 and 132. Moreover,it will be understood that the voltage droop control mode may operateconcurrently with the operation(s) of any other block of FIGS. 2A-2L.

Referring now to FIG. 2L, the regulating operation(s) of Block 220/220′may include injecting active or reactive current (Block 220-3) from thegrid interface power converter 122 to the AC PCC. Such current injectionmay mitigate preexisting harmonics at the AC PCC. For example, theapparatus may detect (Block 220-1), using the meter circuitry 101 and/orthe power electronics circuitry 102, preexisting harmonics at the ACPCC. The apparatus may then determine (Block 220-2), using a processor150, whether to inject harmonic current to the AC PCC. This may includedetermining what frequency and/or magnitude of harmonic current toinject to compensate for the preexisting harmonics. Accordingly, theoperation(s) of Block 220-3 may be performed in response to theoperation(s) of Block 220-1 and/or Block 220-2, and may includeinjecting harmonic current to mitigate the preexisting harmonics. Inparticular, the grid interface power converter 122, using the invertermode, may perform the operation(s) of Block 220-3 in response to theresult of Block 220-1 and/or Block 220-2.

The grid interface power converter 122 may provide voltagesupport/regulation at the AC PCC by actively (a) injecting or consumingreactive power, (b) injecting or consuming real power, or (c) acombination of (a) and (b). The grid interface power converter 122 mayinject or consume reactive power on its own, whereas real power mayinvolve DC power generation and/or storage elements. For example, whenreal power is consumed from the AC PCC, it may be stored in a battery.Moreover, real power that is to be injected into the AC PCC may be takenout of a solar PV or a battery. Accordingly, the grid interface powerconverter 122 is not limited to absorbing reactive power, but rather mayadd or remove real or reactive power to hold the voltage constant at theAC PCC. Such regulation/control of Watt injection and/or consumption andVAR injection and/or consumption may increase the size of the operatingregion that the grid interface power converter 122 may use/select.Energy storage devices, or other DC generation/storage devices connectedto the DC bus 112, may enable this regulation/control.

While the grid interface power converter 122 is performing theoperations of FIG. 2L, or performing the regulating operation(s) of anyother of the FIGS. 2A-2L, the grid interface power converter 122 may becoupled to the DC bus 112, whose voltage may be at any level from 24Volts to 2,000 Volts during the operations. Moreover, a switchingfrequency of the grid interface power converter 122 (e.g., of one ormore power semiconductor devices 122S thereof) may be 10 kilohertz orhigher while performing the regulating operation(s) of any of the FIGS.2A-2L. Such fast switching may provide/improve fault protection, withoutemploying conventional fault protection devices, such as AC and DCmechanical circuit breakers.

The regulating operation(s) of FIGS. 2A-2L may be performedautomatically/autonomously (without control input from outside theapparatus) or may be performed remotely via control input received viathe communications circuitry 103. For example, an adjustment to thevoltage at the DC bus 112 may be determined/commanded by a localizedcommunication node in the field or at a centralized operations center,such as a utility data center including a head end. As an example, auser at the utility data center may use a secure Web interface toconduct/command the adjustment.

In some embodiments, the apparatus, which may be the premise energyrouter PER illustrated in FIGS. 1A and 1B, may connect to an existinghouse secondary service (e.g., a wiring connection 104 of the customer)and an existing utility secondary service (e.g., the low-voltagesecondary service connection 107) on the house. The premise energyrouter PER may provide utility meter functionality, via the metercircuitry 101, and thus may replace an existing utility meter (and mayoptionally replace a meter base) on the house. For example, the premiseenergy router PER may be mountable on the side of the house, and mayhave a housing 106 that is no larger than twenty (20) inches wide,twelve (12) inches deep, and twenty-four (24) inches long (in terms ofvertical height). As an example, an existing utility meter may beremoved, and the premise energy router PER may be installed at thelocation where the utility meter had been before it was removed. Theweight of the premise energy router PER may be forty (40) pounds orlighter (and, in some embodiments, thirty (30) pounds or lighter), suchthat one person can install the premise energy router PER.

Moreover, the DC bus 112, which may be inside the premise energy routerPER and may be coupled to one or more DC loads, may provide a DC powersource into the customer's home and/or may receive DC inputs. Forexample, in some embodiments, the DC bus 112 may both (a) receive a400-Volt DC input (e.g., from a solar device or a battery storage) and(b) provide a 400-Volt DC output to a DC load (e.g., an electric vehiclecharging station). By receiving DC inputs, the DC bus 112 may acceleratethe use of distributed energy resources (e.g., DC loads such as solarpanels, wind energy devices, battery storage devices, electric vehicles,etc.) because the DC bus 112 can obviate the need for a separateinverter, thus saving customers money. Also, the premise energy routerPER may follow such DC loads closely and may sustain a steady voltagelevel despite environmental factors such as a cloud moving over a solargenerator.

In contrast with a static compensator, a DWVCC 122′ according to variousembodiments herein may provide enhanced control, includingmanagement/regulation of the DC bus 112. Moreover, in contrast withcentralized bulk devices at a plant or a substation, a premise energyrouter PER, which may include a DWVCC 122′, according to variousembodiments herein may use hardware that is at or adjacent the customerpremise 120 (e.g., at or adjacent the load). For example, the premiseenergy router PER may not only provide grid support, but also mayintegrate directly on the DC bus 112 of DC storage and/or generationelements DER and may supply capacity. As an example, the rectifier modeof the grid interface power converter 122 may help to enhance supply(e.g., from DC generation and/or storage elements DER on the DC bus 112)and may harmonize with what is demanded/needed on the AC power system.

In some embodiments, the premise energy router PER may provide syntheticinertia, which may improve power quality and system resiliency.Inverters, such as the inverter functionality of the grid interfacepower converter 122, can reduce overall inertia. The premise energyrouter PER, however, can use software and the power electronicscircuitry 102 to artificially insert inertia to match the grid 100.Moreover, in some embodiments, the premise energy router PER may usesynthetic inertia to jumpstart the grid 100 after an outage of the grid100. Such jumpstarting may be similar to jumpstarting the grid 100 witha generator.

Moreover, in some embodiments, the premise energy router PER may beprovided as a retrofit solution that interfaces with an existing (e.g.,third party) inverter, which may not otherwise have access to a DC bus.In such embodiments, the grid interface power converter 122 may beoutside of the housing 106 of the premise energy router PER. The DC bus112 and the power converters 132, however, may still be inside thehousing 106 and may be connected to the grid interface power converter122 that is outside of the housing 106. For example, the grid interfacepower converter 122 that is outside of the housing 106 may include asolar PV inverter that is coupled to a solar PV system. The solar PVsystem may be connected to the DC bus 112 via one of the powerconverters 132 that is inside the housing 106. Accordingly, althoughFIGS. 1E and 1G illustrate a grid interface power converter 122 that isinside the housing 106, the grid interface power converter 122 mayalternatively be an existing, third-party device that is outside of thehousing 106 and that may be coupled to the DC bus 112 that is inside thehousing 106 to provide a retrofit solution.

Specific example embodiments of the present inventive concepts aredescribed herein with reference to the accompanying drawings. Thepresent inventive concepts may, however, be embodied in a variety ofdifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete and will fully conveythe scope of the present inventive concepts to those skilled in the art.In the drawings, like designations refer to like elements. It will beunderstood that when an element is referred to as being “connected,”“coupled,” or “responsive” to another element, it can be directlyconnected, coupled or responsive to the other element or interveningelements may be present. Furthermore, “connected,” “coupled,” or“responsive” as used herein may include wirelessly connected, coupled,or responsive.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the presentinventive concepts. As used herein, the singular forms “a,” “an,” and“the” are intended to include the plural forms as well, unless expresslystated otherwise. It will be further understood that the terms“includes,” “comprises,” “including,” and/or “comprising,” when used inthis specification, specify the presence of stated features, steps,operations, elements, and/or components, but do not preclude thepresence or addition of one or more other features, steps, operations,elements, components, and/or groups thereof. As used herein, the term“and/or” includes any and all combinations of one or more of theassociated listed items. The symbol “/” is also used as a shorthandnotation for “and/or.”

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which these inventive concepts belong.It will be further understood that terms, such as those defined incommonly used dictionaries, should be interpreted as having a meaningthat is consistent with their meaning in the context of the relevant artand the present disclosure, and will not be interpreted in an idealizedor overly formal sense unless expressly so defined herein.

It will also be understood that although the terms “first” and “second”may be used herein to describe various elements, these elements shouldnot be limited by these terms. These terms are only used to distinguishone element from another element. Thus, a first element could be termeda second element, and similarly, a second element may be termed a firstelement without departing from the teachings of the present inventiveconcepts.

Example embodiments of the present inventive concepts may be embodied asnodes, devices, apparatuses, and methods. Accordingly, exampleembodiments of the present inventive concepts may be embodied inhardware and/or in software (including firmware, resident software,micro-code, etc.). Furthermore, example embodiments of the presentinventive concepts may take the form of a computer program productcomprising a non-transitory computer-usable or computer-readable storagemedium having computer-usable or computer-readable program code embodiedin the medium for use by or in connection with an instruction executionsystem. In the context of this document, a computer-usable orcomputer-readable medium may be any medium that can contain, store,communicate, or transport the program for use by or in connection withthe instruction execution system, apparatus, or device.

The computer-usable or computer-readable medium may be, for example butnot limited to, an electronic, magnetic, optical, electromagnetic,infrared, or semiconductor system, apparatus, or device. More specificexamples (a nonexhaustive list) of the computer-readable medium wouldinclude the following: an electrical connection having one or morewires, a portable computer diskette, a random access memory (RAM), aread-only memory (ROM), an erasable programmable read-only memory (EPROMor Flash memory), an optical fiber, and a portable compact discread-only memory (CD-ROM). Note that the computer-usable orcomputer-readable medium could even be paper or another suitable mediumupon which the program is printed, as the program can be electronicallycaptured, via, for instance, optical scanning of the paper or othermedium, then compiled, interpreted, or otherwise processed in a suitablemanner, if necessary, and then stored in a computer memory.

Example embodiments of the present inventive concepts are describedherein with reference to flowchart and/or block diagram illustrations.It will be understood that each block of the flowchart and/or blockdiagram illustrations, and combinations of blocks in the flowchartand/or block diagram illustrations, may be implemented by computerprogram instructions and/or hardware operations. These computer programinstructions may be provided to a processor of a general purposecomputer, a special purpose computer, or other programmable dataprocessing apparatus to produce a machine, such that the instructions,which execute via the processor of the computer or other programmabledata processing apparatus, create means and/or circuits for implementingthe functions specified in the flowchart and/or block diagram block orblocks.

These computer program instructions may also be stored in a computerusable or computer-readable memory that may direct a computer or otherprogrammable data processing apparatus to function in a particularmanner, such that the instructions stored in the computer usable orcomputer-readable memory produce an article of manufacture includinginstructions that implement the functions specified in the flowchartand/or block diagram block or blocks.

The computer program instructions may also be loaded onto a computer orother programmable data processing apparatus to cause a series ofoperational steps to be performed on the computer or other programmableapparatus to produce a computer implemented process such that theinstructions that execute on the computer or other programmableapparatus provide steps for implementing the functions specified in theflowchart and/or block diagram block or blocks.

In the specification, various embodiments of the present inventiveconcepts have been disclosed and, although specific terms are employed,they are used in a generic and descriptive sense only and not forpurposes of limitation. Those skilled in the art will readily appreciatethat many modifications are possible for the disclosed embodimentswithout materially departing from the teachings and advantages of thepresent inventive concepts. The present inventive concepts are definedby the following claims, with equivalents of the claims to be includedtherein.

What is claimed is:
 1. An apparatus comprising: a housing; electricutility meter circuitry in the housing and configured to measure usageof electricity supplied by an electric utility to a premise of acustomer of the electric utility; and power electronics circuitry in thehousing, the power electronics circuitry comprising a dynamic Watt-VARcompensator comprising a grid interface switched mode power converterthat is coupled to an Alternating Current (AC) bus and to a DirectCurrent (DC) bus and that is configured to regulate a voltage of the DCbus.
 2. The apparatus of claim 1, wherein the grid interface switchedmode power converter comprises bidirectional power converter circuitrythat is coupled to the AC bus and to the DC bus and that is configuredto operate in both a power inverter mode and a power rectifier mode. 3.The apparatus of claim 1, wherein the apparatus comprises a PremiseEnergy Router (PER) comprising the electric utility meter circuitry andthe power electronics circuitry at or adjacent the premise of thecustomer, wherein the PER is downstream from a substation that servesthe premise of the customer, wherein the voltage of the DC bus that thegrid interface switched mode power converter is configured to regulatecomprises 24 Volts to 2,000 Volts, and wherein a switching frequency ofthe grid interface switched mode power converter comprises 10 kilohertzor higher.
 4. The apparatus of claim 3, wherein the premise comprises aresidential premise of the customer, wherein a voltage of the AC busthat is coupled to the grid interface switched mode power convertercomprises 120 Volts, 208 Volts, or 240 Volts, and wherein the 120 Volts,208 Volts, or 240 Volts comprises a single-phase, split-phase, orthree-phase voltage.
 5. The apparatus of claim 1, wherein the DC bus isin the apparatus and comprises a shared DC bus that is coupled to aplurality of DC power generation and/or DC energy storage elements atthe premise of the customer.
 6. The apparatus of claim 5, wherein thegrid interface switched mode power converter is configured to convert DCpower received from the plurality of DC power generation and/or DCenergy storage elements via the shared DC bus into AC power.
 7. Theapparatus of claim 6, wherein the grid interface switched mode powerconverter is further configured to inject current to a Point of CommonCoupling (PCC) that is between an AC grid to which the apparatus iscoupled and a load of the premise of the customer, wherein the currentcomprises a direct fundamental and harmonic current and a quadraturefundamental and harmonic current, and wherein the PCC comprises an ACPCC.
 8. The apparatus of claim 5, wherein the grid interface switchedmode power converter comprises single-phase, split-phase, or three-phasepower bidirectional inverter-rectifier circuitry that is coupled to theshared DC bus.
 9. The apparatus of claim 5, wherein the plurality of DCpower generation and/or DC energy storage elements are coupled to theshared DC bus via a plurality of switched mode power converters,respectively, and wherein the shared DC bus is connected between thegrid interface switched mode power converter and each of the pluralityof switched mode power converters.
 10. The apparatus of claim 9, whereinthe plurality of DC power generation and/or DC energy storage elementscomprises: a DC power generation element comprising a solar photovoltaic(PV) system or a fuel cell; and a DC energy storage element comprising abattery or a capacitor.
 11. The apparatus of claim 10, wherein theplurality of switched mode power converters comprises first and secondDC-to-DC power converters that are coupled to the shared DC bus, whereinthe solar PV system or the fuel cell is coupled to the first DC-to-DCpower converter, and wherein the battery or the capacitor is coupled tothe second DC-to-DC power converter.
 12. The apparatus of claim 1,wherein the apparatus is free of any mechanical circuit breaker and freeof any step-up or step-down AC transformer.
 13. The apparatus of claim1, further comprising a DC link capacitor, or a bank of capacitors,coupled to a battery energy storage system.
 14. A method of operating anapparatus connected between a utility secondary service of an electricutility and a wiring connection of a customer at a premise of thecustomer, the method comprising: measuring, using electric utility metercircuitry of the apparatus, usage of electricity supplied by theelectric utility to the premise of the customer; and regulating, using agrid interface switched mode power converter of power electronicscircuitry of a dynamic Watt-VAR compensator of the apparatus, a voltageof a Direct Current (DC) bus in the apparatus, wherein the DC buscomprises a shared DC bus that is coupled to a plurality of DC powergeneration and/or DC energy storage elements at the premise of thecustomer.
 15. The method of claim 14, wherein the regulating comprisesoperating a power inverter mode of the grid interface switched modepower converter, while the grid interface switched mode power converteris coupled to the shared DC bus and is shared by the plurality of DCpower generation and/or DC energy storage elements.
 16. The method ofclaim 15, wherein the regulating further comprises operating a powerrectifier mode of the grid interface switched mode power converter,while the grid interface switched mode power converter is coupled to theshared DC bus and is shared by the plurality of DC power generationand/or DC energy storage elements.
 17. The method of claim 16, whereinthe grid interface switched mode power converter is coupled to anAlternating Current (AC) bus, and wherein the method further comprises:detecting preexisting harmonics at an AC Point of Common Coupling (PCC);and determining harmonic current to inject to the AC PCC to compensatefor the preexisting harmonics.
 18. The method of claim 17, wherein themeasuring and the regulating are performed while the apparatus isdownstream from a substation that serves the premise of the customer andwithout using any step-up or step-down AC transformer in the apparatus,wherein the voltage of the shared DC bus comprises 24 Volts to 2,000Volts while performing the regulating, and wherein a switching frequencyof the grid interface switched mode power converter comprises 10kilohertz or higher, while performing the regulating.
 19. The method ofclaim 18, wherein the premise comprises a residential premise of thecustomer, and wherein the measuring and the regulating are performedwhile the apparatus is at or adjacent the residential premise of thecustomer.
 20. The method of claim 18, wherein the regulating comprisesoperating the grid interface switched mode power converter as a voltagesource, while a plurality of switched mode power converters coupled tothe shared DC bus operates in a current source mode or in a voltagesource mode, wherein the shared DC bus is coupled to the plurality of DCpower generation and/or DC energy storage elements via the plurality ofswitched mode power converters, respectively, and wherein the shared DCbus is connected between the grid interface switched mode powerconverter and each of the plurality of switched mode power converters.21. An apparatus comprising: power electronics circuitry in theapparatus, the power electronics circuitry comprising: a dynamicWatt-VAR compensator comprising bidirectional inverter-rectifiercircuitry that is configured to inject current to an Alternating Current(AC) Point of Common Coupling (PCC); and a Direct Current (DC) buscoupled to both a DC power generation system and a DC energy storagedevice at a premise of a customer of an electric utility, wherein aswitching frequency of the power electronics circuitry comprises 10kilohertz or higher.
 22. The apparatus of claim 21, further comprisingelectric utility meter circuitry in the apparatus and configured tomeasure usage of electricity supplied by the electric utility to thepremise of the customer, wherein the apparatus weighs forty pounds orlighter.
 23. The apparatus of claim 1, wherein the housing is no largerthan twenty inches wide, twelve inches deep, and twenty-four incheslong.